Community (home or birth center) births in the US are on the rise, despite major concerns about home birth safety and frank opposition from ACOG. All available evidence suggests that maternal morbidity is substantially reduced in community settings; however, reports of increased rates of fetal/neonatal death, particularly among home births, are prevalent. Nonetheless, recent economic analyses have suggested that community births are substantially more cost effective, even given an increase in fetal/neonatal adverse outcomes. Given the current level of unsustainable maternity care spending in the US, it is vital that we understand the nuances of community?and particularly, home?birth safety in the US, as community birth may well be a component of future cost-conscious maternity care policies. This project will use a pre-existing, de-identified, medical records-based community birth registry to (1) compare maternal and fetal/neonatal outcomes for planned home vs. planned birth center births in the US, and (2) describe circumstances under which excess fetal and neonatal deaths accrue among planned community births. For Aim 1, n > 80,000 planned home and birth center births will be compared on a variety of maternal and fetal/neonatal outcomes using logistic regression, adjusting for differences in patient populations. Maternal outcomes will include intrapartum transfer to a hospital, cesarean, genital tract trauma, hemorrhage, postpartum transfer to a hospital, and hospitalization in the first 6 weeks. Fetal/neonatal outcomes will include intrapartum death, 5-minute Apgar, meconium aspiration syndrome, respiratory distress syndrome, sepsis, neonatal transfer to a hospital, NICU admission, hospitalization in the first 6 weeks, and neonatal death. It is anticipated that effect modification by midwife credential (certified nurse midwife vs. certified professional midwife) might be observed, in which case stratified results would be presented. A mixed-methods approach will be used for Aim 2, combining the medical records data with transcripts from n = 398 Fetal Infant Mortality Review (FIMR) midwife interviews, allowing unique and necessary insights into not only patient-level variables but also practice- and systems-level variables that may be contributing to excessive intrapartum and neonatal deaths among US home births. Given that the number of US women choosing home birth has increased by >70% in the last 10 years, it is imperative that we make all birth locations as safe as possible. The proposed project will provide evidence regarding two key lingering questions about home birth in the US: namely, whether there are differences between home and birth center (and whether those are driven by risk level, place, or midwife training/credentials), and where, how, and why excess mortality is currently observed among women planning community births. This evidence will then inform future maternity care policy, and will be used by clinicians, payers, and patients to make evidence-informed place of birth decisions.